Continuous hold-down system

ABSTRACT

A hold-down system used to secure a building structure to a foundation, thereby enabling the building to better withstand high winds, earthquakes, and the like. The hold-down system is characterized as being continuous and having stackable, individual take-up devices. A continuous hold-down system may include an anchor extending from the foundation through the various stories of the building structure. One or more take-up devices may limit the motion of selected stories with respect to the anchor. Accordingly, the individual take-up devices, acting alone or in a stacked configuration, compensate for settling, wood shrinkage, wood crushing, and the like throughout the entire height of the building structure.

RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 10/639,304, filed Aug. 12, 2003 and entitled PORTALREINFORCEMENT APPARATUS AND METHOD and a continuation-in-part ofco-pending U.S. patent application Ser. No. 10/602,534, filed Jun. 23,2003 and entitled SHRINKAGE COMPENSATOR FOR BUILDING TIEDOWNS, which isa continuation of U.S. Pat. No. 6,585,469 issued Jul. 1, 2003 andentitled SHRINKAGE COMPENSATOR FOR BUILDING TIEDOWNS, which is acontinuation of U.S. Pat. No. 6,390,747 issued May 21, 2002 and entitledSHRINKAGE COMPENSATOR FOR BUILDING TIEDOWNS.

BACKGROUND

1. Field of the Invention

The present invention relates to building construction, and morespecifically, to apparatus for anchoring shear walls to foundations andlower floors.

2. Background

Strong winds and earthquakes subject walls and others elements of abuilding to tremendous forces. If these forces are not distributed tothe proper elements or structures capable of withstanding such force,the building may be torn apart. Foundations are often the strongestelement of a building. Securely tying the walls of a building to thefoundation greatly improves structural performance during periods ofstrong wind or earthquake. Securement promotes single body motion andlimits whiplash amplification that often results in structural failure.

Under extreme conditions, a building may be violently loaded or shakenback and forth in a lateral (side to side) direction. If a shear wall istightly restrained at its base, loads may be smoothly transferred to thefoundation. The loads may then be resolved in the foundation, where theyappear as tension and compression forces.

Buildings are often composed of long walls, (walls with a length greaterthan the height) and short walls (walls that have a length shorter thanthe height). The tendency for a wall to lift vertically off a foundationis inversely proportional to the length of the wall. Tall narrow shearwalls, which may be found in nearly all homes, act as lever arms and maymagnify an imposed load. In certain instances, the actual load on thesecurement system may be magnified to several times the originallyimposed load.

The as-built building is generally not the building that will besustaining loads induced by wind or by earthquake shaking. Woodcomponents of the building structure, including floors, joists, sillplates, top plates, and studs, will shrink. Shrinkage varies greatly butranges typically from about one-quarter inch under the best ofconditions, to well over one inch depending on the total cross-grainstack up (depth) of wood.

Wall securement may prevent lateral and vertical motion between thewalls and the foundation. Additionally, it may be necessary to supportthe wall against forces that would tend to distort the wall's generalrectangular shape. Building codes often require external and loadbearing walls to be shear resistant by providing a plywood plane tosupport shear forces that may be imposed on the wall. Many times,building codes also require lateral and vertical securement of a wall tothe foundation. Lateral and vertical securement may be accomplished byemploying hold-downs, also referred to as tie-downs.

Hold-down systems are employed to secure walls of upper levels to wallsof lower levels, as well as walls to foundations. Again the principle isto secure the entire structure to the foundation where structural forcescan best be resolved. However, lower levels can present amplification ofstructural weaknesses to upper levels. If a hold-down system installedon a given level cannot compensate for all shrinkage and crushingaffecting that level, structural weaknesses may be amplified on adjacentlevels. Hold-down systems need to be able to compensate for structuralweaknesses throughout the structure, and not just within a given level.

Moreover, hold-down systems can be difficult to install and expensive tofabricate. Some hold-down systems require assembly within narrowtolerances, making assembly difficult and time consuming. Otherhold-down systems cannot compensate for structural weaknesses throughoutthe structure, causing an overload of a hold-down system on a givenlevel. Accordingly, a need exists for a hold-down system that may beeasily installed and utilizes the full potential of the system over theentire structure. It would be a further advancement to provide ahold-down system that may be produced and installed in greaterquantities with greater speed and less expense.

BRIEF SUMMARY AND OBJECTS OF THE INVENTION

It is an object of the present invention to provide a continuoushold-down system that may be easily and quickly installed.

It is a further object of the present invention to provide a hold-downsystem that may be mass produced inexpensively.

In certain embodiments, the apparatus and method in accordance with thepresent invention may include a foundation with an anchor, which anchoris composed of threaded rods coupled together and extending through oneor more levels of a building or structure. The anchor provides a basisfor the individual components of the continuous hold-down system. Thetake-up units used in the system help maintain tension throughout thesystem, essentially securing the entire structure to the foundation.Securing the structure to the foundation enables the structure to betterwithstand various forces acting on the structure. These forces aretransferred to the foundation where they can be dissipated moreefficiently.

While previous hold-down systems may be considered useful for similarpurposes, the continuous hold-down system described herein is a moreeffective and efficient system. Previous hold-down systems may not becontinuous, thereby isolating each individual level of the building. Thecontinuous nature of the current invention allows the system tocompensate for shrinkage or crushing which may occur on any level of thebuilding. Thus, if shrinkage or crushing on one level exceeds thecapacity of the system on that level, the system on other levels cancompensate for the excess.

Another feature of this particular continuous hold-down system is thatthe individual take-up units used in the system are stackable, more thanone take-up unit may be stacked providing greater ability to compensatefor shrinkage and crushing. This is especially helpful in the continuoussystem because the system is capable of compensating for shrinkage andcrushing which may occur on any level of the building. Therefore, if thetop level of the building has a couple of take-up units stacked on topof each other, those units can compensate for any excess shrinkage orcrushing throughout the building. This can also be especially helpful onupper levels of a building because shrinkage and crushing that may occuron lower levels tend to be accentuated on upper levels.

A continuous hold-down system as described herein can also be used forthe specific purpose of supporting a portal frame. The system can beinstalled on either side of a portal frame, thereby making the portalframe self-cinching. A shear wall is generally a frame that is furthersupported by attaching a shear plane (e.g. a sheet of wood) over theframe. The added support helps maintain the original, intended shape ofthe wall. However, a portal frames an opening lacking such shearsupport. It does not allow the supporting sheet to be attached, therebylosing that support. The portal becomes more susceptible to shearingforces and a change of shape. As the portal is stressed, the framingmaterial of the portal can be damaged or crushed thereby losing tensionin the support system. The take-up units in accordance with theinvention automatically and continuously compensate for any crushing.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects and features of the present inventionwill become more fully apparent from the following description andappended claims, taken in conjunction with the accompanying drawings.Understanding that these drawings depict only typical embodiments of theinvention and are, therefore, not to be considered limiting of itsscope, the invention will be described with additional specificity anddetail through use of the accompanying drawings in which:

FIG. 1 is a perspective view of a continuous hold-down system;

FIG. 2 is a partially cut-away, perspective view of a coupler connectingtwo threaded rods of the same diameter (2A) and a coupler connecting twothreaded rods of different diameters (2B);

FIG. 3 is an exploded view of an automatic take-up unit;

FIG. 4 is a perspective view of varied uses of the automatic take-upunits securing a sill plate to a foundation, including allowing thetake-up unit to rest directly upon the sill plate, or using a bracket tosupport the take-up unit;

FIG. 5 is a perspective view of two automatic take-up units stacked ontop of each other;

FIG. 6 is a perspective view of one embodiment of a hold-down system;

FIG. 7 is a perspective view of another embodiment of a hold-downsystem;

FIG. 8 is a perspective view of another embodiment of a hold-downsystem;

FIG. 9 is an elevation cross-sectional view of a self-cinching portalframe;

FIG. 10 is an elevation cross-sectional view of a self-cinching portalframe;

FIG. 11 is a perspective view of shearing force acting on a continuoushold-down system illustrating how crushing may occur;

FIG. 12 is an elevation cross-sectional view of one embodiment of aself-cinching portal frame; and

FIG. 13 is an elevation cross-sectional view of one embodiment of aself-cinching portal frame.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

It will be readily understood that the components of the presentinvention, as generally described and illustrated in the Figures herein,may be arranged and designed in a wide variety of differentconfigurations. Thus, the following more detailed description of theembodiments of the system and method of the present invention, asrepresented in FIGS. 1 through 13, is not intended to limit the scope ofthe invention. The scope of the invention is as broad as claimed herein.The illustrations are merely representative of certain, illustrativeembodiments of the invention. Those embodiments of the invention will bebest understood by reference to the drawings, wherein like parts aredesignated by like numerals throughout.

Several Figures display an automatic take-up unit. This device isdescribed fully in U.S. Pat. No. 6,390,747 issued May 21, 2002, to thisinventor, and incorporated herein by reference.

Those of ordinary skill in the art will, of course, appreciate thatvarious modifications to the details of the Figures may easily be madewithout departing from the essential characteristics of the invention.Thus, the following description of the Figures is intended only by wayof example, and simply illustrates certain embodiments consistent withthe invention.

In discussing the Figures, it may be advantageous to establish areliable coordinate system, referring to FIG. 1, to aid in thedescription of several of the embodiments in accordance with the presentinvention. Coordinate axes 11 may be defined by a wall as longitudinal11 a along the wall, lateral 11 b through or across the wall, andtransverse 11 c up and down the wall height. The longitudinal 11 a,lateral 11 b, and transverse directions 11 c are directionssubstantially orthogonal to one another. In the description to follow,the embodiments will be oriented so that they are aligned and primarilyconfigured to oppose or transfer longitudinal loads of shearing forcesby precluding or resisting motion in a transverse direction 11 c.Embodiments in accordance with the present invention are secured in alongitudinal direction to resist or transfer forces and loads along morethan one axis simultaneously. Several embodiments, however, may beparticularly well suited to resisting or transferring loads in a givendirection, and as previously mentioned, this principal axis for shearloading will typically be substantially the transverse axis 11 c.

A continuous hold-down system 10 in accordance with the presentinvention may include a foundation 12 with an anchor 14 extendingtransversely 11 c from the foundation 12, the anchor 14 also extendingtransversely 11c through a surface to be retained and engaging a take-upunit 40 secured in place along the anchor 14 by a retainer 42. Theanchor 14 may be composed of a single threaded rod 18 or multiplethreaded rods 18 secured together with a coupler 16.

The foundation 12 may be any structural foundation 12 that may be usedin construction, having a lateral thickness and extending longitudinally11 a. Typical materials for the foundation 12 include concrete, steel,stone, and wood. The anchor 14 generally begins as a threaded rod 18embedded in a concrete foundation 12 (often welded to reinforcing bar)and extending transversely 11 c out from the foundation 12. The anchor14 may be composed of numerous threaded rods 18. A coupler 16 may beattached to the distal end (away from the foundation 12) of one threadedrod 18 and the proximal end (toward the foundation 12) of anotherthreaded rod 18, thereby extending the anchor 14 transversely 11 c.

Using this method, the anchor 14 is extended through successive levelsof the structure and provides for transferring to the foundation 12forces applied to the structure 70, or shear wall 70. Typical materialsfor the threaded rod 18 include steel, other metals, reinforcedcomposites, and plastic. Typical threaded rods 18 may be continuouslythreaded along the length of the rod 18, or be threaded only on the endportions of the rod 18 leaving the center portion smooth. Typicalmaterials for the coupler 16 include steel and plastic, and willgenerally match the material used for the threaded rod 18. The coupler16 can join threaded rods 18 of the same diameter (as shown in FIG. 2A),or the coupler 16 can join threaded rods 18 of varying diameters (asshown in FIG. 2B).

A sill plate 20 is a member proximate the foundation 12 and extendingparallel or longitudinally 11 a with the foundation 12. The sill plate20 provides a base for vertical framing members 22, which extendtransversely 11 c. The vertical framing members 22 have a proximate end(toward the foundation 12) and a distal end opposite. A top plate 24 isattached to the vertical framing members 22 at the distal end of theframing members 22 and extends longitudinally 11 a. A shear wall 70 maybe formed by attaching a sheet or sheets of plywood or other structuralmaterial to the sill plate 20, vertical framing members 22 (e.g. studs22), and top plate 24. Numerous top plates 24 may be used. However, atop plate 24 may support a header 26, extending longitudinally 11 a, andone or more trusses 28, extending laterally 11 b. The header 26 and thebeams 28 or trusses 28 (e.g. joists 28, beams 28, etc.) may supportflooring 30. This configuration generally describes an initial level ofa structure.

A base plate 36 is a member proximate the flooring 30 and extendinglongitudinally 11 a. The base plate 36 serves a function similar to thesill plate 20 by providing a base for vertical framing members 22extending transversely 11 c. The vertical framing members 22 have aproximate end (toward the foundation 12) and a distal end opposite. Atop plate 24 is attached to the vertical framing members 22 at thedistal end of the framing members 22 and extends longitudinally 11 a. Ashear wall 70 may be formed by attaching a sheet or sheets of plywood orother structural material to the base plate 36, vertical framing members22, and top plate 24. Numerous top plates 24 may be used. However, a topplate 24 may support a header 26, extending longitudinally 11 a, and oneor more trusses 28, extending laterally 11 b. The header 26 and thetrusses 28 may support flooring 30. This configuration generallydescribes a subsequent level of a structure. Obviously, subsequentlevels may be added to other subsequent levels creating a multi-levelstructure.

The sill plate 20, the vertical framing member 22, the top plate 24, thebase plate 32, the header 26, and the trusses 28 make up the framingcomponents and may be any structural support member used inconstruction. They may have a variety of cross-sectional configurations,such as rectangular, circular, I-beam, or any other suitable design.Typical materials include wood and metal. However, embodiments inaccordance with the present invention may be applied to any materialhaving the desired structural characteristics.

The anchor 14 extends transversely 11 c through the sill plate 20 of aninitial level. The sill plate 20 may be secured to the foundation 12using a take-up unit 40. The take-up unit 40 may be placed around theanchor and rest upon the sill plate 20, or rest upon a bearing plate 36.The bearing plate 36 may be in the form of a plate or washer and istypically steel, but may be made of any suitable material. The take-upunit 40 is axially independent of the anchor 14, thereby facilitatingquick and easy installation of the take-up unit 40. The take-up unit 40is secured in place along the anchor 14 between the surface to beretained, sill plate 20 or bearing plate 36, and a retainer 42 proximatethe take-up unit 40. The retainer 42 threadedly engages the anchor 14 tokeep the take-up unit 40 in contact with the sill plate 20 or bearingplate 36. The take-up unit 40 extends transversely 11 c to maintaincontact between the sill plate 20 and the foundation 12.

The anchor 14 may be extended using a coupler 16 and a threaded rod 18.The coupler 16 may be threadedly attached to the anchor 14, and thenthreadedly attach the threaded rod 18 to the coupler 16. This method canbe used to extend the anchor 14 through the sill plate 20 and top plate24 of the initial level of a structure. The use of a take-up unit 40 onthe initial level as previously described is optional, depending on thedesign of the building and the intention of the builder. A take-up unit40 on every level has been shown effective.

The anchor 14 extends transversely 11 c through the base plate 32 of asubsequent level. The base plate 32 may be secured to the structureusing a take-up unit 40. The take-up unit 40 may be placed around theanchor and rest upon the base plate 32, or rest upon a bearing plate 36.which bearing plate 36 may be in the form of a plate or washer and istypically steel, but may be any suitable material. The take-up unit 40is axially independent of the anchor 14, thereby sliding along theanchor and facilitating quick and easy installation of the take-up unit40. The take-up unit 40 is secured in place along the anchor 14 betweenthe surface to be retained, base plate 32 or bearing plate 36, and aretainer 42 proximate the, take-up unit 40. The retainer 42, such as anut 42, threadedly engages the anchor 14 to keep the take-up unit 40 incontact with the base plate 32 or bearing plate 36. The take-up unit 40extends transversely 11 c to maintain contact between the base plate 20and the structure.

The anchor 14 may be extended using a coupler 16 and a threaded rod 18.The coupler 16 may be threadedly attached to the anchor 14, and then thethreaded rod 18 may be threadedly attached to the coupler 16. Thismethod can be used to extend the anchor 14 through the base plate 32 andtop plate 24 of a subsequent level of a structure. The use of a take-upunit 40 on a subsequent level as previously described is optionaldepending on the design of the building and the intention of thebuilder. Obviously, this method can be used to secure any subsequentlevel to the structure, thereby making it possible to transfer to thefoundation 12 forces applied to the structure. However, the rods 18nearest the foundation 12 should be sized to support the additive loadsof subsequent levels thereabove.

FIG. 3 depicts the individual components of a take-up unit 40. The threemajor components of the take-up unit 40 are the base 44, the slide 46,and the bias element 50, which bias element 50 is typically a spring.The base 44 and slide 46 are engaged using the threads 48. The biaselement 50 provides a self-energizing force to urge rotation of theslide 46 relative the base 44 in a direction to effect an increase inheight of the take-up unit 40, the increase in height occurringtransversely 11 c. The bias element 50 may be attached to the base 44using a tab 52. The bias element 50 may be pre-loaded before the tab 53is attached to the slide 46 using a tab fastener 54. The base 44 andslide 46 may be rotated relative to each other until the trigger 56 maybe engaged within the socket 58. Once the trigger 56 is engaged, thetake-up unit 40 is ready for installation. The anchor 14 extends throughthe aperture 60, and the trigger 56 is removed to activate the take-upunit 40. A more detailed description of the take-up unit is available inU.S. Pat. No. 6,390,747.

The components of the continuous hold-down system 10 used on any givenlevel of the structure may vary. FIG. 1 illustrates a variety ofconfigurations. In one embodiment, the initial level may have a take-upunit 40 resting on a bearing plate 36 securing the sill plate 20 to thefoundation 12. In one embodiment, the anchor 14 may be extended throughany subsequent level of a structure without using a take-up unit 40 tosecure the base plate 32 to the structure. In one embodiment, a take-upunit 40 may rest on a bearing plate 36 securing a base plate 32, withthe anchor 14 extended by a coupler 16 and a threaded rod 18. In oneembodiment, two take-up units 40 are stacked transversely 11 c on thefinal level of the structure to compensate for shrinkage or crushingthat may exceed the capacity of take-up units 40 on preceding levels.

FIG. 1 also shows how a take-up unit 40 may be installed transversely 11c along an anchor 14 between levels of a structure. A blocking board 34may be installed between vertical framing members 22, thereby providinga surface to be restrained and a position where a take-up unit 40 may beinstalled.

FIG. 4 illustrates how a take-up unit 40 may rest directly on the sillplate 20 when securing the sill plate 20 to the foundation 12. FIG. 4also illustrates how a bracket 64 may be used to provide a bearingsurface 66 to support a take-up unit 40 on an initial level. The bracket64 is secured to a vertical framing member 22 using bracket fasteners68. The take-up unit 40 urges the transverse 11 c movement of thevertical framing member 22 toward the foundation 12.

As shown in FIG. 5, two take-up units 40 may be stacked transversely 11c on the initial level of a structure. As shown in FIG. 6, two take-upunits 40 may be stacked transversely 11 c on a subsequent level of astructure. Stacking two take-up units 40 on any level increases thecapacity to compensate for shrinkage or crushing on that level as wellas other levels throughout the system. It may also be advantageous tostack two take-up units 40 on the upper levels of a structure becauseproblems with shrinkage and crushing created on lower levels can beaccentuated on upper levels. Also, the continuous nature of the system10 allows compensation for shrinkage and crushing to occur on any level,thereby compensating for any level where the associated take-up unit 40may have fully extended.

As shown in FIG. 7, a bracket 64 may be installed between verticalframing members 22, thereby providing a position where a take-up 40 maybe installed. The bracket 64 may be attached to the vertical framingmembers 22 using bracket fasteners 68. The bracket 64 provides a bearingsurface 66 upon which a take-up unit 40 may be installed. FIG. 7 alsoshows the use of brackets 64 and take-up units 40 on opposing sides of atransition to a subsequent level of a structure. This configurationwould help secure one level of the structure to the adjacent level.Installation of a take-up unit 40 proximate the bearing surface 62 urgesthe vertical framing members 22, to which the bracket 64 has beenattached, in a transverse 11 c direction away from the retainer 42. Theretainer 42 secures the take-up unit 40 to the anchor 14.

In one embodiment, as illustrated particularly in FIG. 8, a blockingboard 34 is further supported by vertical framing members 22. Theblocking board 34 provides a surface to be restrained between levels ofa building. One or more vertical framing members 22 may be used, likepillars, underneath and on either side of the blocking board 34 in orderto support the blocking board 34. The vertical framing members 22providing support underneath the blocking board 34 keep the blockingboard 34 from being pulled transversely 11 c as tension is applied tothe continuous hold-down system 10. While one take-up unit 40 may beinstalled to restrain the blocking board 34, two take-up units 40 may bealso be used to increase the capacity of the continuous hold-down system10.

The anchor 14 may be extended through the initial level of the structurewithout using a take-up unit 40 to secure the sill plate 20 to thefoundation 12. This configuration is generally used near portals 72, andis illustrated in FIGS. 9, 10, 12 and 13.

One use of the continuous, threaded hold-down system 10 is providingsupport for portal frames. As described earlier, a shear wall 70 iscomposed of a frame and a sheet of supporting material such as plywoodattached to the frame providing extra support. A shear wall 70 isdesigned to help the wall support shearing loads in a longitudinaldirection and maintain its shape. If a force is applied longitudinally11 a to a shear wall 70, the structure of the shear wall 70 will resistthis force, without distorting or lifting, and the shape and position ofthe shear wall 70 will be maintained.

Portal frames are basically shear walls 70 that have a portal 72. Theportal 72 is typically a door or a window, but may be any portal 72 thatdoes not allow the use of a continuous sheeting material to complete theshear wall 70. The portal 72 will diminish the resistance to shearingforces, or longitudinal 11 a forces. The use of a continuous hold-downsystem 10 provides extra support to shear walls 70 that have a portal72.

As shown in FIG. 9, the continuous hold-down system 10 may be assembledon either side of a doorway 72 or portal 72. The anchor 14 may have afoundation assembly 74 embedded in the foundation 12. The anchor 14extends transversely 11 c from the foundation 12. A coupler 16 may bethreadedly attached to the anchor 14 and a threaded rod 18 may bethreadedly attached to the coupler 16, thereby extending the anchor 14transversely 11 c above the level of the top plate(s) 24. A take-up unit40 may be installed and rest on the top plate 24, or a bearing plate 36.A retainer 42 is then threadedly attached to the anchor 14 securing thetake-up unit 40 in place. This method may be repeated for either side ofthe portal 72.

In one embodiment, cables 76 are attached to the sill plate 20 and thetop plate 24 on either side of the portal 72. The cables 76 travel fromthe sill plate 20 to the top plate 24 longitudinally 11 a andtransversely 11 c, thus providing triangulated support to the portal 72through tensile loading of the cables 76. Attaching the cables 76 inthis manner gives the cables 76 the appearance on an “X” circumscribedby the vertical framing members 22, the sill plate 20, and the top plate24. Again, cables 76 can be used in this manner on either side of aportal 72. In another embodiment, shown in FIG. 10, a shear wall 70 oneither side (or both) of the portal 72 provides shear support to theportal 72.

The use of the continuous, threaded hold-down system 10 in this mannerresults in a self-cinching portal frame. As shown in FIG. 11, a shearingforce, or longitudinal 11 a force, may distort the shape of a portal 72and adjacent shear walls 70. As the portal 72 is distorted in shape, thecontinuous, threaded hold-down system 10 may begin to angle in thedirection of the longitudinal 11 a force, thereby causing crushing ofthe top plate 24 at the point where the take-up unit 40 or bearing plate36 contacts the top plate 24. The angle of distortion is somewhatexaggerated in FIG. 11 to better illustrate the crushing of the topplate 24 caused by the longitudinal 11 a force.

As the longitudinal 11 a force abates and the portal 72 returns to itsoriginal position, the decreased dimension due to crushing may result ina loss of tension in the continuous, threaded hold-down system 10.However, the take-up unit 40 expands to compensate for any crushing andmaintains the desired tension in the continuous hold-down system 10. Itis apparent that the continuous hold-down system 10 as described wouldcompensate for substantially any loss of tension resulting fromshrinkage or from crushing caused by any longitudinal 11 a force appliedto the portal 72.

The continuous hold-down system 10 may be used on portals 72 varying insize and purpose. FIG. 12 illustrates the use of the continuoushold-down system 10 to produce a self-cinching garage door portal 72.FIG. 13 illustrates the use of the continuous hold-down system 10 in awall containing window portals 72 and doorway portals 72.

From the above discussion, it will be appreciated that the presentinvention provides novel apparatus and methods directed to a hold-downfor securing first and second support members to an anchoring device.The hold-down may have a first and a second flange, each flange havingmultiple securement apertures to facilitate securement to the first andsecond support members respectively. A base may connect the first andsecond flange and have an aperture for admitting and securing theanchoring device. When loaded in application, the first and secondflanges may be configured to be loaded in tension.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrative,and not restrictive. The scope of the invention is, therefore, indicatedby the appended claims, rather than by the foregoing description. Allchanges that come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

1. An assembly comprising: a foundation; a first wall supported abovethe foundation and comprising a first bearing surface; an anchorextending from the foundation and through the first bearing surface; afirst retainer engaging the anchor at a first distance above the firstbearing surface; and a first take-up device positioned and expandable tofill the first distance, the first take-up device comprising a base, aslide, the base and slide mutually threaded to provide relative lineartranslation during multiple revolutions of relative rotation of theslide with respect to the base, the base and slide being formed to havea clearance hole to receive the anchor therethrough, and a bias elementurging the relative rotation in a direction selected to provide axialexpansion.
 2. The assembly of claim 1, wherein the first wall furthercomprises a sill plate extending horizontally, a top plate extendinghorizontally, and at least one support member extending verticallybetween the sill plate and the top plate
 3. The assembly of claim 2,wherein the first bearing surface comprises one of a top surface of thetop plate and a top surface of the sill plate.
 4. The assembly of claim2, wherein the first wall further comprises an intermediate memberextending horizontally between a first support member of the at leastone support member and a second support member of the at least onesupport member at a location between the sill plate and top plate. 5.The assembly of claim 4, wherein the first bearing surface comprises atop surface of the intermediate member.
 6. The assembly of claim 1,further comprising a second wall supported above the first wall, thesecond wall comprising a second bearing surface.
 7. The assembly ofclaim 6, wherein the anchor further extends through the second bearingsurface.
 8. The assembly of claim 7, further comprising a secondretainer engaging the anchor at a second distance above the secondbearing surface.
 9. The assembly of claim 8, further comprising a secondtake-up device positioned and expandable to fill the second distance.10. The assembly of claim 9, wherein the second take-up device comprisesa base, a slide, the base and slide mutually threaded to providerelative linear translation during multiple revolutions of relativerotation of the slide with respect to the base, the base and slide beingformed to have a clearance hole to receive the anchor therethrough, anda bias element urging the relative rotation in a direction selected toprovide axial expansion.
 11. The assembly of claim 10, wherein the firsttake-up device is positioned to transfer to the anchor a first loadcorresponding substantially exclusively to a dynamic loading imposed onthe first wall.
 12. The assembly of claim 11, wherein the second take-updevice is positioned to transfer to the anchor a second loadcorresponding substantially exclusively to a dynamic loading imposed onthe second wall.
 13. An assembly comprising: a foundation; a wallsupported above the foundation and comprising a bearing surface; ananchor extending from the foundation and through the bearing surface; aretainer engaging the anchor at a distance above the bearing surface;and a first take-up device positioned and expandable to fill thedistance, the first take-up device comprising a base, a slide, the baseand slide mutually threaded to provide relative linear translationduring multiple revolutions of relative rotation of the slide withrespect to the base, the base and slide being formed to have a clearancehole to receive the anchor therethrough, and a bias element urging therelative rotation in a direction selected to provide axial expansion.14. The assembly of claim 13, wherein the wall corresponds to one of afirst story and another story above the first story.
 15. The assembly ofclaim 14, wherein the wall further comprises a sill plate extendinghorizontally, a top plate extending horizontally, and at least onesupport member extending vertically between the sill plate and the topplate
 16. The assembly of claim 15, wherein the bearing surfacecomprises one of a top surface of the top plate and a top surface of thesill plate.
 17. The assembly of claim 15, wherein the wall furthercomprises an intermediate member extending horizontally between a firstsupport member of the at least one support member and a second supportmember of the at least one support member at a location between the sillplate and top plate.
 18. The assembly of claim 17, wherein the bearingsurface comprises a top surface of the intermediate member.
 19. Theassembly of claim 13, wherein the anchor comprises an anchor boltextending from within the foundation, at least one threaded rod, and acoupler connecting the at least one threaded rod to the anchor bolt. 20.An assembly comprising: a foundation; a wall supported above thefoundation and comprising a bearing surface; an anchor extending fromthe foundation and through the bearing surface; a retainer engaging theanchor at a distance above the bearing surface; and a first take-updevice; a second take-up device stacked on top of the first take-updevice; the first and second take-up devices positioned and expandableto collectively fill the distance; and the first and second take-updevices each comprising a base, a slide, the base and slide mutuallythreaded to provide relative linear translation during multiplerevolutions of relative rotation of the slide with respect to the base,the base and slide being formed to have a clearance hole to receive theanchor therethrough, and a bias element urging the relative rotation ina direction selected to provide axial expansion.